Last May, after devastating rail crashes made more damaging by a particular kind of crude oil being carried, the U.S. Department of Transportation issued an emergency order.
It said if more than a million gallons of that crude was moving on the rails, local emergency crews had to be notified.
California's legislature tried to make that kind of notice permanent - not just for oil but also for 25 of the most toxic substances traveling the rails.
But there may be a hitch in California's new law.
"Yesterday was a good example of a derailment of a toxic substance, except it didn't leak and there was no immediate threat. But imagine that same rail car going through the Feather River Canyon and polluting the water source for millions of people in California," Kelly Huston, Deputy Director of the California Office of Emergency Services said.
A new state law in effect as of January 1 is supposed to reduce the worry of some of those what-ifs, especially when it comes to the growing number of rail cars shuttling through the Sacramento region, loaded with the kind of highly flammable Bakken crude oil that's exploded in other train derailments.
"Accidents happen, but our job as a society is to make sure accidents don't become tragedies," Assemblyman Mike Gatto said.
The Glendale area democrat co-sponsored AB 380, the new law requiring rail companies to notify emergency responders of what threats could be riding the rails in their area.
"What's unique about this legislation is that we're working with the railroads to try to provide more real-time information...sort of like an Amtrak schedule," Huston said.
Right now, those details come to emergency crews after the fact, not in advance when they could prepare.
The other unfortunately unique thing about this law is that rail carriers can still argue they don't have to follow it, even though implementation is supposed to be complete by January 31.
"It is a delicate balance because the railroads are federally regulated which means federal laws pre-empt state laws in most cases," Huston said.
So even though California's done all it can, it remains to be seen if rail companies will cooperate with a law that could save lives.
Under the continuing federal emergency order, Cal OES gets the shipment information from rail carriers.
Huston would like to create a system that first responders can log in to themselves and get the information real-time.
The effort would not compromise a oil producer's proprietary information, they said.